Abstract The timing and mechanisms of deformation along the northwestern Tibetan Plateau remain poorly constrained. Here we present new low-temperature thermochronological data from the western Songpan-Ganzi terrane, a key yet understudied region of the plateau interior. Apatite fission track and zircon and apatite (U-Th)/He ages cluster in the late Eocene-Oligocene, and thermal history modeling indicates moderate to rapid cooling and exhumation during this interval, followed by limited post-Oligocene cooling. These results suggest that deformation and exhumation were primarily concentrated in the late Eocene-Oligocene, with subsequent limited cooling and exhumation across the high-elevation, low-relief plateau interior. In contrast, younger cooling ages from the West Kunlun Mountains indicate that Neogene deformation and exhumation were localized along the plateau margin. Together, these observations highlight strongly diachronous deformation histories across northern Tibetan Plateau and provide new constraints on the spatiotemporal evolution of plateau development.
He et al. (Wed,) studied this question.